package com.liuxing.javaSpringBoot.interceptor;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Created by IntelliJ IDEA.
 * 自动封装template 路径
 * 约定：目标页面的相对路径地址与path地址一致
 * @File ViewMappingInterceptor.java
 * @Auth liuxing
 * @Date 2021/8/23 13:26
 * @Email liuxing997@foxmail.com
 */
@Component
public class ViewMappingInterceptor implements HandlerInterceptor {

    private final static Logger LOGGER = LoggerFactory.getLogger(ViewMappingInterceptor.class);

    @Override
    public boolean preHandle(HttpServletRequest request,
                             HttpServletResponse response,
                             Object handler) throws Exception {
        LOGGER.debug("=======ViewMappingInterceptor pre Handle ======");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request,
                           HttpServletResponse response,
                           Object handler,
                           ModelAndView modelAndView) throws Exception {
        LOGGER.debug("=======ViewMappingInterceptor post Handle ======");
        //判断请求是否换回view，如果是rest接口｜｜ redirect｜｜forward不做处理
        if (modelAndView == null
                || modelAndView.getViewName().startsWith("redirect")
                || modelAndView.getViewName().startsWith("forward")){
            return;
        }
        //从请求中得到path
        String path =  request.getServletPath();
        //判断modelMap中是否设置template，有则无需设置
        String template = (String) modelAndView.getModelMap().get("template");
        //在modelMap中设置template， 值为path
        if (StringUtils.isBlank(template)){
            path = path.startsWith("/") ? path.substring(1) : path;
            modelAndView.getModelMap().addAttribute("template",path);
        }
    }

    @Override
    public void afterCompletion(HttpServletRequest request,
                                HttpServletResponse response,
                                Object handler,
                                Exception ex) throws Exception {
        LOGGER.debug("=======ViewMappingInterceptor after Handle ======");
    }
}
